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In biology, '''sex''' refers to the categorization of organisms (or their parts) with regard to the role they play in reproduction. When a species reproduces sexually, it usually does so by producing two types of gametes that have to come together to form a new member of the species. One type of gamete is large and non-mobile (ova), whereas the other type is small and | In biology, '''sex''' refers to the categorization of organisms (or their parts) with regard to the role they play in reproduction. When a species reproduces sexually, it usually does so by producing two types of gametes that have to come together to form a new member of the species. One type of gamete is large and non-mobile (ova), whereas the other type is small and motile (spermia). When an organism or an organ produces large and non-mobile gametes, it's called '''female'''. If it produces small and motile gametes, it's called '''male'''. | ||
In most mammals, in particular humans, female members of the species can be identified by having two X chromosomes, ovaries, a uterus and a vagina. The ovaries produce ova (also called egg cells), which may be fertilized into a zygote, which travels to the uterus to develop into an embryo, a fetus, and ultimately a baby which is brought to the world through the vaginal canal. Males can be identified by having an X and a Y chromosome, testes (testicles) and a penis. The testes produce sperm, which are ejaculated into the vagina during sexual intercourse, from where they might travel towards the ova to fertilize them. | In most mammals, in particular humans, female members of the species can be identified by having two X chromosomes, ovaries, a uterus and a vagina. The ovaries produce ova (also called egg cells), which may be fertilized into a zygote, which travels to the uterus to develop into an embryo, a fetus, and ultimately a baby which is brought to the world through the vaginal canal. Males can be identified by having an X and a Y chromosome, testes (testicles) and a penis. The testes produce sperm, which are ejaculated into the vagina during sexual intercourse, from where they might travel towards the ova to fertilize them. |
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